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Interfacial engineering of perovskite films has been the main strategies in improving the efficiency and stability of perovskite solar cells (PSCs). In this study, three new donor‐acceptor (D–A)‐type interfacial dipole (DAID) molecules with hole‐transporting and different anchoring units are designed and employed in PSCs. The formation of interface dipoles by the DAID molecules on the perovskite film can efficiently modulate the energy level alignment, improve charge extraction, and reduce non‐radiative recombination. Among the three DAID molecules, TPA‐BAM with amide group exhibits the best chemical and optoelectrical properties, achieving a champion PCE of 25.29 % with the enhanced open‐circuit voltage of 1.174 V and fill factor of 84.34 %, due to the reduced defect density and improved interfacial hole extraction. Meanwhile, the operational stability of the unencapsulated device has been significantly improved. Our study provides a prospect for rationalized screening of interfacial dipole materials for efficient and stable PSCs. [ABSTRACT FROM AUTHOR]

In the pursuit of highly efficient perovskite solar cells, spiro‐OMeTAD has demonstrated recorded power conversion efficiencies (PCEs), however, the stability issue remains one of the bottlenecks constraining its commercial development. In this study, we successfully synthesize a novel self‐polymerized spiro‐type interfacial molecule, termed v‐spiro. The linearly arranged molecule exhibits stronger intermolecular interactions and higher intrinsic hole mobility compared to spiro‐OMeTAD. Importantly, the vinyl groups in v‐spiro enable in situ polymerization, forming a polymeric protective layer on the perovskite film surface, which proves highly effective in suppressing moisture degradation and ion migration. Utilizing these advantages, poly‐v‐spiro‐based device achieves an outstanding efficiency of 24.54 %, with an enhanced open‐circuit voltage of 1.173 V and a fill factor of 81.11 %, owing to the reduced defect density, energy level alignment and efficient interfacial hole extraction. Furthermore, the operational stability of unencapsulated devices is significantly enhanced, maintaining initial efficiencies above 90 % even after 2000 hours under approximately 60 % humidity or 1250 hours under continuous AM 1.5G sunlight exposure. This work presents a comprehensive approach to achieving both high efficiency and long‐term stability in PSCs through innovative interfacial design. [ABSTRACT FROM AUTHOR]

Lead halide perovskites always emerge complex interactions among different elemental ions, which lead to multiple intrinsic imperfections. Elemental defects, such as amine, Pb, and I vacancies at A‐, B‐, and X‐sites, are main issues to deteriorate perovskite solar cells (PSCs). Unfortunately, most previous passivators can only temporarily fix partial inactive vacancies as sacrificial agents. Herein, we propose a recovery agent, ferrocene (Fc), which can form a one‐dimensional perovskite with adequate steric cavities and suitable dissociation energy to recover all elemental defects back to active light‐harvesting perovskites, and regenerate Fc itself meanwhile. Based on this perpetual chain‐reaction cycle, corresponding PSCs maintain >10 000‐hour lifetime in inert condition and >1000‐hour durabilities under various extreme environments, including continuous 85 °C heating, 50 % relative humidity wetting, and 1‐sun light soaking. [ABSTRACT FROM AUTHOR]

Keywords: chain-reaction cycle; defects; ferrocene; perovskites; solar cells EN chain-reaction cycle defects ferrocene perovskites solar cells 1 2 2 06/14/22 20220620 NES 220620 It has come to the authors attention that incorrect versions of Figures 1, 2, and 4 were inadvertently used during the final stages of manuscript preparation. Berichtigung: Ferrocene-Induced Perpetual Recovery on All Elemental Defects in Perovskite Solar Cells Chain-reaction cycle, defects, ferrocene, perovskites, solar cells. [Extracted from the article]